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Quantum Bigfoot 4320AT

I remember these drives... they became available around the time I had a Cyrix CPU and an S3 graphics card. We were not willing to cough up for a proper Pentium ~200mhz. Anyway, these were the budget drives also, making use of space instead of enhancing technology to fit more bytes in smaller places!

The Quantum Bigfoot pictured above is the 4320AT model, meaning it's listed capacity is 4.3gb. Of course, partitions never manage to give a drive's entire space to the user, so a FAT32 partition via USB-IDE via Windows 10 formatted out to 4.03gb.

This drive usually wouldn't even warrant a mention, but this model has a specifically interesting feature. It also seems quite rare, since googling didn't result in too many versions of this style of Bigfoot. Looking above, you'll see a transparent sticker over a window in the drive. It's actually a window that exposes the read heads! That's a really strong sticker... or so I hope, I haven't tried to remove it. Regardless, it lets you actually see the head has stopped when it's powered off... better yet, you can even watch it move when it's in operation!

Totally random! And amazing to watch!

Atari Controller Test Rig

Long-story-short, I've got a new night-job, bringing a large quantity of Atari-related paraphernalia back to life. I've done it before with the 2600 Jr, and I'm ready to do it again, and again, and again, with this batch.

First up is a box of gamepads and controllers. My initial plan was to get one of the Atari units in a known-state, and then test the controllers from there... but that could lead to issues if the console wasn't actually 100%. Instead, why not just rig up a DB-9 port to a simple 5v LED circuit to test each button?

Google will produce a crap-load of results for Atari Joystick Pinout, so find one of them and get started. I chose this one. It turns out the controllers are very straight forward... they just act as a conduit to ground. Pin 8 is the common ground wire and all buttons (directional-pad inclusive) just join their respective pin to this wire.

The above rig was therefore constructed. Voltage is supplied from my desktop power supply and a miriad of LEDs were selected from the junk box. A selection of 48ohm resistors tie them all to the 5v rail. Their anodes all go to a respective pin on the controller port... starting with Up, Down, Left, Right, A, B from the left-most green LED. Of course, A and B are contentious, as the 2600 only utilises one fire button. Even better, the DB-9 socket also supports trigger, so that's the clear LED placed awkwardly on the left-hand side.

First controller to be tested was an Atari gamepad and it instantly misbehaved. Upon opening it, I found that both A and B buttons were tied high with resistors.

A little googlin' declares that these gamepads are actually for the Atari 7800, which supported two buttons. They've nicely made them backwards compatible though, allowing either button to be the standard button for the Atari 2600 jr. Regardless, those pull-up resistors meant that my A and B button LEDs were always dimly-lit!

Upon pressing either button, their respective LED fully-lit, and so did the left-most trigger LED. This makes me think that trigger is the actual 'button' for the Atari 2600 Jr and A/B are for newer systems. Regardless, the unit still had an issue. For those keenly-observing the photos up until this point, you'll have guessed that the directional pad's right button was crapola. It worked sometimes... and then it worked all the time when you jiggled the cable at the entry-point to the controller. So, what to do? Truncate!

Take a good length off, away from the game pad. Cable fractures, when entering casing/housing, are a very standard thing. Usually, very much like this unit, there's 'protection' inside the casing where the cable is held in-place to prevent it from being wrenched out and putting pressure on internal components. This 'protection' in this case is a zig-zag of pins to hold the cable in place without putting serious pressure on it.

For this unit, this 'protection' has done its job and kept the internals safe, but the cable has instead formed an issue directly after it exits the controller case. Here, thanks to humans like me, waving the controller around (rather than pressing the correct buttons), causes undue stress internally and ruptures the wires. In this case, it actually severed the wire that conducts a directional-right press.

As above, strip the newly truncated cable and tin all ends. Once done, de-solder the original chunk of cable, re-soldering the newly cut ends in the same order. Make sure to keep the white bridging wire between both PCBs. Finally, run the cable through the zig-zag and hold it there for a bit to make sure it understands its new role. If you just place it and let go then the cable tends to want to return to it's standard straight-line form. It's actually tough for a thick cable to make those curves, but as mentioned above, it's for the sake of the guts of the contorller.

Finally, test, test, test and test again! Ah... that GREEN RIGHT LED is beautiful.

Atari 2600 Jr – Recapping + Controllers + Composite

Another one of these little units came across my workbench. This time it was a full set with two joysticks and a lot of games... including a boxed version of Frogger! I'd played with one of these before in my previous-previous apartment, so it must be nearly 4 years ago that I met my first Atari. This one wasn't as clean-and-tidy as the previous version, but it still worked nicely.

The first task was to upgrade the unit to composite output, so I jumped over to my previous post on the topic. I purchased all the components needed from Jaycar and, just before I was about to solder to the pins on the IC, realised that the actual mod instructions showed you where to solder. Not to the pins of the IC, but to the legs of the surrounding resistors.... the diagram is even colour-coded. I therefore also didn't have to scratch back a ground pad either!

In no time, the composite signal was being sent out and my TV Tuner card was picking it up nicely. Whilst I was performing the mod, I noticed that the surrounding electrolytic capacitors weren't looking the cleanest, so I replaced those too. After another trip to Jaycar, purchasing 4x 4.7uf and 1x 2200uf (unfortunately they didn't stock double-ended!) capacitors, I went about removing the old ones and soldering in the new ones. Solder wick really works well here to clean the holes in the PCB prior installing the new capacitors. The positive pins are also nicely marked on the PCB.

With everything replaced, there was no noticeable change in video quality or system stability, but neither were a problem to start with. This was more for longevity! I slapped in the multi-cart and tried Pitfall out. The Quickshot controller worked OK, but felt very sticky and the buttons weren't responding to each keypress... what to do? Pull it apart.

The board was not clean... so I grabbed some isopropyl wipes and gave it a good once-over. I also re-soldered the main A button wire as it had previously been compressed by the case and didn't look like it'd hold out much longer. With the unit back together, I could now jump on-command with the button on the base, but the trigger button up top wasn't overly responsive. The stick itself has three screws that hold it together, so I popped them out to have a look.

Turns out the top button had been mashed to within an inch of its life and the previous players had actually punched a hole in the PCB, removing the trace that the button was meant to make contact with.

A little bit of solder was added, which caused a height increase of the pad. I was slightly concerned that this would mean the button could mis-fire, but the spring prevented that from occurring... instead it just meant the button didn't have to travel as far to make contact. I could now jump through Pitfall reliably! Mario Bros was also now a lot more fun!

I suppose the final step now is to find a new ball for the top of this chewed-on stick!